Expanding clamping means



March 8, 1932.

F. J. JARVIS EXPANDING CLAMPING MEANS Filed July 11, 1930 E 132 1.15 28 i Z8 4 Zlwmntoz wank J. Jarvis and fixtures forcasters and similardevices I Patented .Mar; 8 1932 i l i 1 .p

c we; or BALMERMASSACHUSETTSQA con-renames on MASSACHUSETTS i i EHANDINGYCQAMHNGLMEANS p i r Application filed July" 1-1, This "invention relates to V improvements expanding holding or clamping means and has particular referenceto such expanding,

means for'securinga casterjstem or analogous Y5 device; to the article towhiclrit is attached, and has suhjectnmatter common ,Withmy; c-' pen-ding application filed July 11,1930, Serial No. 4673371 q j H I The: principal, object ofthe" invention is ioj to provide improved expanding means adapted to fit -ta'ching sockets orfixturest c c y r 7 Another object of theinv'ention is to pro-- Vide. simple and inexpensive Connectingc'ior V 15, clamping means easilyadjusted to different sizes and shapes :of attaching sockets or fixturesfj F is Another object of the invention is toJpro- W 'vide simple, inexpensive and positively :operable clamping means adapted 'tokpermita casterstemor likeobject to be fitted ltoattaching sockets or fixtures of diiferenti sizes andcharacteristics. v

Another object'of the inventionis to pro videimpro'ved means forattaehingand de taching the clamping means. "I-

I Anotherohjectof the invention is to vprovide animproved caster that may bjeceasily f n andfquickly attached: to or detached. from T3 attaching means of'difierent sizes andchar-r acteristics provided: on the articles to which the caster is to be attached. 7 Y l I Other objects and advantageszofathe invention will become apparent from thefol lowing: description taken in connectionwith the acompanying drawings; It is apparent that many changes inl'the details of construction and arrangementof parts may be made withoutdepartingfromthespirit of the invention expressed in the following claims. The preferred formsonly have been described and illustrated by way of explanation hence I do not'wish to belimited to the exact details shownand described; 7 1 I It is Well known that the attaching" sockets vary in size and shape and in other characteristics." It is, therefore, one of the main ob jec'ts of this inventionto provide expansible means "easily and positively operable to acconnnodate these conditions.

various sizes and shapes of at- I nut to the expanding {m ma Jnavis, examine, MASSACHUSETTS, essrenon To Mav s i nniilinvrs, 3

found-from experience M in hospitals and in y stitutions tnat demented andeccentric pa tients often detach ca sters and hurl thehi throughiwindows or otherwise use them a s 1 It 1s,xth'erefore, another weapons of attack. object of the invention to provide securing means ofa nature not obviously and easily detached without special appliances adapted to; the purpose; Another: prime object is to PTO? vide such expansihle means i that are simple in construction and-operation and" inexpen sive' ofproduct onw It w ll readily ,heseen that the adaptability tojvarious sizes and shapes of attaching means' s deration in the manufacture and distrihu tlonof such devices, both from the standpoint of economy and convenience.

- Referring to the drawings; in which sim-' ilar referencecharacters refer to similar parts throughout is alprime con Fig. I is a perspective yiew of a caster gem bodying the invention with some of the parts separated and removed;

Fig. II is a longitudinalcross-sectionshow 111g thejcaster stem insertedin the attaching socket; "i

Fig; III Iisfacross-section on line I of Fig-II," 1 v F ig; IV is a cross-section on line IV-JY ofFig. II looking in the "direction of the arrows; f I 7- I Fig; V is a partial "view in cross-section showing a modified formof connectingthe member adjacent the top ofthe stem;and

Fig. VI is a partial view in cross section showing a different form of lock nut beneath I the bearing. i i N ,1 W 1 The numeral 1 indicates the socket or at taching connection which is secured to the article to which the caster or similar device is to 'be attached; as shownthis is atube and may be square in cross-section orofother shape. I The caster wheel 2' is rotatably mounted on the axle pin?) in the usual manner in the caster bracket or fork 4 which is secured'at 5 to the shell 6 of thebearing'f, the parts being preferablycompressed together. The

' position over them.

surface at the tube 1..

shown in Fig.

swim Above the spider expansion plate 17 and Passing through the inner bearing block 11 is the caster stem '13 having the shouldered head 14 and a'threaded upper portion 15. The shoulder of the head 14 bears on the under side of positionthe stem 13 in relatedposition .to the parts of the caster. Surrounding the stem 13 and resting on the upperend of the innerv bearing-block ll-is the washer 16 which abuts the lower end of the attaching socket 1. Above the washer 16 and slidable on the stem 13 is the expansible spider plate 17 having .a

ion 18 resting onthe washer 16 and a plurality of outwardly and upwardly cxtending leg members 19 terminating in contactingfiacets 20 adapted to bear on the inner of the attaching tube 1.

also slidable on the stem 13 is a second expansible spider plate 21 having the body portion 22 and a plurality minating against the l 19 of the member of the piate17. The legs of the plates 17 and 21 are shown as four'i-n number :Eor each plate formingthe sides of asquare. There may be a greater or less number of legs and'the'y may be either straight or rounded to suit theinner Surrounding the stem 13 and above the upper spider plate 21 is the spacer'tube 26, the

lower endo'f which rests onithe section 22 of the upper spider plate 21. Above the tube 26 and resting thereon is another spider plate member 27 similar in construction to the spider plate member 17 and above this anoth e'r spider plate member 28 similar in construction to spider plate 21. Above the spider plate 28 is the threaded nut 30 to which the spider plate 28 is attached at 34' by compressing the member 28 into a groove 'therein or by other means, as V. If desired the nut '30 may besepara'te from the plate 28, simply resting thereon, as shown in Figs. I and II. The spider plates 27 and 28 are the same in construction and operation as the spider plates '17 and 21. I g

In the shouldered head 1 1 of the stem'13 may be made a polygonal socket recess 31, see

3 Fig. III, adapted to fit the polygonal shaped wrench arm 32, or if desired a nut 33, Fig. VI,

may be employed instead. If the nut is used an ordinary wrench may be utilized for its operation. s

; i The method of operation is as follows: To

insert the stem 13 and its fittingsinto the shortening the'distance the inner bearing block 11 'to of outwardly and downwardly extending leg members23 ter-.

tube 1, turn the stem 13 with the wrench 32 7 until the parts are loosened on the stem. This action turns the threaded stem in the nut 30, allowing the extending legs of the spiders to contract inwardly towards the stem, the said spiders being made of resilient or springy material. Then insert the stem 13 with its fittingsflinto the tube 1 until the washer 16 engages the lower end of the tube. Then turn the wrench in the opposite direction; This drives the stem 13 through the nut 30 7 between the nut 30 and washer lfir This action forces the legs of the-plate 21-against the legs of the plate 17 and the legs of the plate 27 against the legs of the 'plate28, forcing the facets 20 of the outer platesintocontact with the inner surface of the attaching tube 1 "to such an extent that the stem 13 is held securely inthe tube 1. To withdraw the stem 18 from the tube '1 the action is the reverse. i If the device.

I gers or am ordinary wrench, .a desirable consideration where 'the devices are. to be used in places accessible to demented persons or desperate prisoners, etc. It is apparent too that this device may be used f0! sockets either circular or other shape in cross-section, and of di flerent sizes. It is also apparent that the expanding 'fieatures are of the very simplest construction and exceedingly economicaltoproduce. I

From the foregoing description it will be I seen that I have provided simple, efiicient and exceedingly economical means for carrying out all of the objects of the invention and of obtaining the advantages thereof.

Having described my invention, I

1. In a device of the character described in combination with an attaching stem, an 'expansionplate on'the stem having outwardly inclined expansion arms, a second expansion plate on the stem having outwardly inclined expansion arms terminating against the expansion arms of the first expansion plate and operable means which will change the distance between said expansion plates to extend or retract the. said arms as the case may be.

2. In .a device of the character described in combination "with an attaching stem, :0, pair of expansion members on the stem separated by a spacer member, each of said expansion members comprising an'expansion plate on the stem havingoutwardly inclined expansion arms and a second expansion plate on the stem having outwardly inclined expansion arms terminating against the expansion arms of the first expansion plate, and operative means which will change the distance between the expansion pla'tesof each expansion member to extend or retract the expansion arms thereof as the case may 3. In a device of the character described,

having outwardly -a caster fork, a caster wheel rotatably mounted in the fork,'a cast-er stem rotatably supported by the fork, an expansion plate on'the stem having outwardly inclined expansion arms, a second expansion plate on the stem inclined expansion arms I terminating against the expansion arms of which will bythe fork, a

the first expansion plate and operable means change the distance between said expansion plates to extendor retractthe said arms as the case may be. r I r I 4. In a device of the character described, a

in the fork, a caster stem rotatably supported on the stem separated by a spacer member,

each of said expansion members comprising an 'expanslon plate on" the stem having outwardly inclined expansion arms and a second expansion plate on the stem having outwardly inclined expansion arms terminating against the-expansion arms of the firstex-r pansion plate, and operative means which will change the distance between the, expansion-plates of each expansion member to extend or retract the expansion arms thereof as thecase may be. e V

FRANK J. JARVIS.

caster fork, a caster wheel rotatably mounted 1 pair of-expansion members 

